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Nach einer kritischen Betrachtung der Begriffsbestimmung „Spannungsriskorrosion” wird die Phanomenologie derselben gekennzeichnet unter Abgrenzung gegen ahnliche Erscheinungen wie z.B. Schadigung durch diffundierenden Wasserstoff, Druckwasserstoffangriff bei erhohter Temperatur und Lotbruch. Es werden die Voraussetzungen fur das Eintreten der Spannungsriskorrosion aufgezeigt und die verschiedenen Stufen des Schadigungsvorganges gekennzeichnet. Aus dem umfangreichen Problemkreis der Spannungsriskorrosion werden einige Punkte herausgestellt, welche sowohl den Mechanismus der Spannungsriskorrosion illustrieren als auch die grose Zahl der Einflusfaktoren aufzeigen. Die transkristalline Form wird als besonders kennzeichnend fur das Wesen der Spannungsriskorrosion angesehen. Der neueste Stand der Ansatze zur Erklarung der Vorgange wird insbesondere in Anknupfung an Studien an austenitischen Stahlen besprochen. Die Mitwirkung von physikalischen Effekten wird wahrscheinlich gemacht unter besonderer Erwahnung der Spannungsriskorrosion bei hochploymeren Kunststoffen. An Hand des Auswahlprinzips hinsichtlich anfalliger Stellen im Werkstoff und spezifischer Angriffsmittel wird die Frage nach den Lucken der theoretischen Klarstellung aufgeworfen. Schlieslich wird auf die Notwendigkeit weiterer Forschungen hingewiesen und die Praxis aufgefordert, systematischer als bisher die Erfahrungen zusammenzutragen. A synopsis of the sphere of stress cracking corrosion. Part II. Consideration of a fundamental nature on the problem of stress corrosion cracking Following a critical survey of the term “stress corrosion cracking” the phenomenology of this type of corrosion is characterized in order to distinguish it from similar phenomena as e.g. damage caused by diffusing hydrogen, attack by high pressure hydrogen at elevated temperature and cracking due to soldering. The author further delinetaes the conditions necessary for the formation of stress corrosion cracking, and shows the individual steps of this deteriovation process. Some points are emphasized from among the comprehensive group of problems associated with stress corrosion cracking; these points illustrate the mechanism of stress corrosion cracking as well as the vast number of factors influencing this type of corrosion. The transcrystalline form is regarded as a particularly characteristic features of stress corrosion cracking. The latest state of attempts at elucidating these phenomena is discussed, with particular reference to studies on austenitic steels. It is shown that the cooperation of physical effects is probable; in this context particular reference is made to the stress corrosion cracking of plastic polymers. On the basis of the criterion involving the selection of spots susceptible to stress corrosion cracking in the material and specfic aggressive media the question is raised where there are open gaps in the theoretical explanation. Finally the necessity of further research is pointed out and an appeal is made to all those concerned to make available and collect the results of practical experience in a more systematic way than before.

The equation phi(cc s$sup -1$ cm$sup -1$ atm/sup -1/2/) = 6.1 x 10$sup - 2$ ($Root$ P/$Root$ M) exp [-13,200/RT] was found to apply for D, T, and H in Type 201 nickel at 297 to 652$sup 0$K and 1 to 275 atm. The diffusivity is not concentration dependent. (DLC)

Exposure to hydrogen at 900 F and 1800 psi for 2900 hr does not weaken 2 1/4 Cr:1 Mo steel. At 1000 F, however, both 1 1/4 Cr: 1/2 Mo and 2 1/4 Cr:1 Mo steel suffer some loss of strength, the effect being greater in the former steel. Welded samples appear to have about the same strength as unwelded.

A description is given of a hydrogen gas target, which has been designed to operate at a pressure of 450 lb/in2 and at a temperature of -70? C, to be used in studies of x-ray scattering from hydrogen using a nuclear photograph emulsion technique. The choice of material for the entrance window and the high-pressure sealing of flanges is discussed.

In engine laboratory of Musashi I.T., R and D work on the hydrogen fuels engines was commenced in 1970, and the most important event was participation in SEED (Student Engineered Economy Design) Rally along the west coast in U.S.A., 1975. After that many LH2 (liquid hydrogen) powered cars have been developed there. Latest car Musashi 6 has a system in which the high pressure hydrogen is injected onto the hot surface igniter near TDC. The high pressure hydrogen is produced by LH2 pump, and engine power-up is achieved by the turbocharger.

In the microcavity storage system, high pressure hydrogen is stored in hollow, glass microspheres, 5 to 150 ..mu..m. This report presents the results of an experimental study to evaluate the performance of commercially available microspheres for this application. Eight grades were evaluated and their characteristics are presented. A substantial fraction of the microsphere beds survived the conditions of storing hydrogen at pressures of 400 atm. establishing that the concept of high pressure hydrogen storage is feasible. Information was gathered on the properties of the survivor microspheres. Processes for their selective recovery are being investigated.

Prof. Watase will be remembered among Japan’s scientific community as a great leader in cosmic ray physics. He was one of the leaders who revitalized activities in Japan’s physics, which was deeply damaged by the war, and helped to build it up to the present level.

This report describes a small, laboratory scale, pumping system which is used to compress hydrogen or its isotopes to high pressures. The system, designed for filling micro-targets for laser-fusion experiments, has successfully pumped small amounts of deuterium and deuterium-tritium mixes to pressures up to 138 Mpa (20,000 psi). The pressure is generated by the decomposition of vanadium dihydride but other possible metal-hydride systems are discussed. Operation and safety aspects are also discussed.

This paper gives the results of about twenty full scale purification tests made on the silica gel purifiers installed in the large CEL-NBS hydrogen liquefier for final purification of electrolytic hydrogen. These results are compared with predicted capacities made by W. T. Ziegler of the Georgia Institute of Technology, The increasing interest in purification of hydrogen for many uses, including liquefaction, prompted this evaluation program.

Glasses synthesized under high pressure of hydrogen showed resistance to certain effects of irradiation. Paramagnetic and light-absorption effects associated with irradiated glasses were diminished by a factor as large as 20 in some glasses. Irradiation increases the concentration of hydroxyl ions, as evidenced by increased absorption in the 2.7-micron (3700 cm(-1)) infrared region for hydrogen-silica glasses.

Recently, the measurement of threshold stress intensity factors for various low alloy ferritic steels in high-pressure hydrogen gas of 103 MPa was performed, and it was revealed that the subcritical cracking threshold under rising displacement was lower than the subcritical cracking threshold for crack arrest under constant displacement. These experimental results demonstrate the importance of the testing method for evaluating the fracture properties in high-pressure hydrogen gas. We measured the subcritical cracking threshold under rising displacement for ASME SA-372 Grade J ferritic steels in high-pressure hydrogen gas at pressure up to 115MPa. In contrast to other reported procedures where the applied displacement was increased continuously, in this study crack length was determined using an unloading elastic compliance method. The values of the subcritical cracking threshold measured by the unloading elastic compliance method are consistent with previous measurements in which the applied displacement continuously increased. These results suggest the possibility that subcritical cracking thresholds do not depend on the applied displacement path, i.e., periodic unloading vs. continuously rising displacement.Copyright © 2014 by ASME

A novel Steel Concrete Composite Vessel (SCCV) was designed and engineered for stationary high-pressure gaseous hydrogen storage applications. SCCV comprises four major innovations: (1) flexible modular design for storage stations for scalability to meet different storage pressure and capacity needs, flexibility for cost optimization, and system reliability and safety, (2) composite storage vessel design and construction with an inner steel vessel encased in a pre-stressed and reinforced outer concrete shellshell, (3) layered steel vessel wall and vent holes to address the hydrogen embrittlement (HE) problem by design, and (4) integrated sensor system to monitor the structural integrity and operation status of the storage system. Together, these innovations form an integrated approach to make the SCCV cost competitive and inherently safe for stationary high-pressure hydrogen storage services. A demonstration SCCV has been designed and fabricated to demonstrate its technical feasibility. Capable of storing approximately 89 kg of gaseous hydrogen at 6250 psi (430 bar), the demonstration vessel was designed to include all major features of SCCV design and fabricated with today’s manufacturing technologies and code/standard requirements. Two crucial tests have been performed on this demonstration vessel. A hydro-test was successfully carried out to 8950 psi per ASME VIII-2 requirements. The cyclic hydrogen pressure test between 2000 psi and 6000 psi is currently being performed to validate its use for high-pressure hydrogen storage. Multiple sensors, such as pressure sensors and strain gages, were incorporated in the demonstration SCCV to collect information to validate the design and operation of SCCV. Key design parameters and test data on its performance are summarized in this paper.

廃棄プラスチックのケミカルリサイクルについて, ポリプロピレン (PP) の水添接触分解油化を回分式で行った。触媒には5wt%鉄担持活性炭を用い, 反応温度673～693K, 初期H2圧4.0MPaにおいて1時間反応を行ったところ, 固体生成物が著しく減少し, 液収率の向上が見られた。同時に, 重質留分の接触水素化分解によって生成油は熱分解の場合より軽質化した。また, 683Kにおいて反応ガスをH2とArで比較したところ, 反応時間0.5～1.0hにおいてH2による分解の促進が確認された。さらに, 683Kでの反応において初期H2圧を変化させたところ, ～3.0MPaにおいてはH2圧の増加とともに分解が進行したが, 4.0MPa～では分解が抑制されたことから, PPの接触分解においてH2が大きく関与していることが確かめられた。

In high pressure hydrogen atmosphere (above 1 GPa) perfectly formed non-ferromagnetic hydrides of Ni-7 at % Cr and Ni-40 at % Cu deliver by decomposition forms of restoration of the ferromagnetism known as precipitations in common alloys. Together with a mass-spectroscopic analysis of the H content the magnetic measurements allow determination of the maximal atomic ratio ( n H / n Me ) max as well as the minimal H amount for filling up the d-band.

Three orders of Stokes and six orders of anti-Stokes in several tenth atm H2 SRS are obtained simultaneously. The stimulated Raman process (SRP) and four-wave parametric process in SRS energy transfer are investigated in this pper. The off-axis Stokes ring and on-axis anti-Stokes spot are studied experimentally in more detail here, and the experimental results are discussed by means of parametric and nonparametric-theory of nonlinear optics.